Clamator glandariusgreat spotted cuckoo

Geographic Range

The Great Spotted Cuckoo extend throughout Southern Europe and Africa. They are distributed through east Africa to Somalia, Sudan and Senegal, Mediterranean Africa, Asia Minor and parts of Mediterranean Europe (chiefly Spain) (Cramp, 1985).

Habitat

The natural habitat of the Great Spotted Cuckoo is woodland or savanna. They are usually observed in semi-arid areas, rocky hillsides, dry cultivation (Middle East), or among scattered trees in open country (Europe). (Maclean, 1985, Payne, 1997).

Physical Description

Length: 37-40 cm (Maclean, 1985) The top of the head and crest are pale, silvery gray and blend gradually into pale grayish or olive brown on the back and wings. The wings are long and wide at the base. The dorsal surface has a spotted appearance due to white tipped wing coverts and back feathers. The long tail feathers are a dark gray, broadly tipped with white. The primaries are a dark, olive-brown and have a metallic luster. The throat, neck, and underparts are a creamy-white (Rowan, 1983). The bill is a dark bluish-gray to black and is paler on the basal half of the lower mandible. It is wide at the base and has slit-like nostrils. The iris is colored brown and is encircled with a bright, red eye-ring. The legs and toes are tinted leaden gray (Cramp, 1985).

There is some geographic variation in size. Birds located in the Middle East are similar in size to those of Egypt. However, C. glandarius in Spain, Portugal, and Northwest Africa display a slightly shorter wing and tail span. Furthermore, populations breeding in the northern region of South Africa through Tanzania are the smallest in all measurements (Cramp, 1985).

Reproduction

Breeding: During the early summer, male and female C. glandarius can be seen flying and foraging together, often chasing each other and frequently exchanging calls. These calls consist of a chattering sound proceeded by a rolling noise (Cramp, 1985). Their calling wanes during the breeding season which, over most of their range, is restricted to the four months, October through January (Rowan, 1983). Breeding peaks in October in Zimbabwe, November/December in Natal, and not until February in Namibia. The male usually arrives first at the breeding grounds. The birds regularly form pairs and are usually monogamous; however, in occasional instances various males have selected the same female. Monogamous pairs in captivity form a pair-bond and accompany each other constantly. They are seen perched side by side, where they frequently touch bills and call softly to each other (Cramp, 1985).

Courtship and Copulation:

Courtship is performed by feeding and invariably accompanies copulation. The male finds an insect such as a caterpillar, grasshopper, or moth, and then mounts the receptive female (Rowan, 1983). The female indicates her interest by rhythmically jerking her body while keeping her wings closed. The female then grasps the food in her bill as the male bends his head downward. Both birds maintain a grip on the prey, which balances the male. The male settles low on the female and clutches both sides of her body with his legs. Copulation can last up to two minutes. When copulation is successfully completed, the insect is relinquished to the female (Cramp, 1985).

Egg Laying:

The Great Spotted Cuckoo is parasitic and usually chooses to lay its eggs in the nest of the Pied Crow. However, cuckoos make use of open and hole nesting starlings, especially in Somalia, Sudan, and Zambia (Rowan, 1983). Before the female lays her eggs, she takes the initiative and searches for a host's nest. Once the host's nest is chosen, the male may assist in distracting the host. The pair often distracts by loud calling. In some cases, the male approaches the host's nest conspicuously, calling as it flies from bush to bush. The female can then make a silent advance into the nest under the cover of vegetation. The female has been observed to lay her eggs while sitting on the nest rim. She often removes an egg of the host when depositing her own or damages it cracking or holing the shell. The female can lay as many as 13 eggs in one nest, and 15-25 eggs in one season (Cramp, 1985). The incubation period is about 12-15 days and is four to five days shorter than its host. After hatching, the young C. glandarius grows up and is cared for by its host (Payne, 1997). It remains in the nest for approximately 18 days (Friedman, 1948).

Behavior

Migration occursonly at the northern and southern ends of the breeding range (southern Europe and the Middle East; southern Africa). Residents in between either make short distance movements or remain in the same area year round. European Great Spotted Cuckoos mostly migrate to Africa while some move to South Spain (Cramp, 1985). Migration begins by adults in mid June while juveniles leave in July or August (Payne, 1997). Great Spotted Cuckoos travel singly, in pairs, and often in larger groups with three or four birds. Male and female tend to associate closely and often form bonds (Rowan, 1983). They are noisy and conspicuous and spend much time in the tops of trees (Maclean, 1985). C. glandarius does exhibit antagonistic behavior. During the breeding season, males follow each other around and engage in various fights. The birds threaten one another by fanning their tails and raising their crests. They are highly aggressive when defending their breeding territories and often pull out each others feathers. Male C. glandarius often rebuff other males by display-flight. The male usually flies from treetops, climbing steeply, with a fanned tail, accompanied by an advertised call. He then descends quickly into a tree canopy. This behavior may also be used to attract a female (Cramp, 1985).

Communication and Perception

Food Habits

C. glandarius are exclusively insectivores. Their diet consists of mainly hairy or spiny caterpillars. The caterpillars are dressed by removing their hairs before consumption. Additionally, these cuckoos eat some termites, grasshoppers, moths, and lizards (Payne, 1997). The Great Spotted Cuckoo generally feeds on the ground. They ordinarily hop through the foliage with their tails raised searching intently for prey. Periodically, they make long bounds while hunting and flutter in pursuit of fast moving victims (Rowan, 1983).

Economic Importance for Humans: Positive

The Great Spotted Cuckoo is not generally recognized as having any positive economic importance. However, it is possible that its consumption of caterpillars may reduce the amount of crop pests destroying fields and produce.

Economic Importance for Humans: Negative

The Great Spotted Cuckoo has affected the success of magpie chicks in a parasitized nest. The magpie chicks grow more slowly and fledge at lower weights (Payne, 1997). C. glandarius may also harm some of the other species whose nests it occupies.

Conservation Status

C. glandarius is gernerally unobservable and rare throughout the majority of its range. Nevertheless, in the larger areas it inhabits, it can be seen frequently. The species population is expanding in South Europe and the Middle East; however, it is decreasing in Egypt where it is now rare as a breeding bird. The Great Spotted Cuckoo has also disappeared as a breeder in North West Africa (Payne, 1997).

Other Comments

The calls of the Great Spotted Cuckoo are loud, grating, and assorted. These birds are noisiest when they first arrive at their final destinations during breeding season. This is most evident in Zimbabwe, South Africa, and Namibia. Their clamor lessens as the season progresses. Their most familiar cry is keeeow keeeow keeeow. This may be used to attract females. However, the female produces a bubbling or chuckling sound burroo, burroo. Both the male and female produce a high pitched alarm note chick-chick-chick. When harassed, C. glandarius generate a great variety of clucks, croaks, grunts, chattering, and quacking sounds in shorts bursts (Rowan, 1983). Futhermore, in Zimbabwe, the Great Spotted Cuckoo is one of several supposed rain birds. Its calling has been said to be a sign that rain will fall (Rowan, 1983).

Contributors

Ilana Gonik (author), University of Michigan-Ann Arbor.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

tactile

uses touch to communicate

visual

uses sight to communicate

References

Cramp, Stanley 1985. Handbook of the Birds of Europe the Middle East and North Africa. Volume IV. Oxford University Press, New York, pp 391-400.

Friedman, Herbert 1948. The Parasitic Cuckoos of Africa. Washington Academy of Sciences, Washington, D.C., pp 1-19.

Liverside, R. and Mclachlan, G.R. 1978. Robert's Birds of Southern African. John Voelcker Bird Book Fund, Cape Town, pp 247.

Maclean, Gordon 1985. Robert's Birds of Southern Africa. John Volcker Bird Book Fund, Cape Town, pp 331-332.

Payne, R.B. 1997. Handbook of the Birds of the World. Volume IV. Lynx Edictions, Barcelona, pp 508.

Rowan, M.K. 1983. The Doves, Parrots, Louries and Cuckoos of Southern Africa. Croom Helm Ltd, South Africa, pp 279-289.

Wyllie, Ian 1981. The Cuckoo. Universe Books, New York.